Feeding mechanism for sewing-machines



R. BECKER.

FEEDING MECHANISM FOR SEWING MACHINES.

APPLICATION FILED N0v.19. 191s.

1,89%07 1 4 v Patented Nov 15, 1921.,

3 SHEETS-SHEET I.

INVENTOR W m M BY a? 7 ATTORNEY WITNESSES:

APPLICATION FILED NOV: I9, I918.

2 9 1 5 1 V O N N .m m a D1 3 SHEETS-SHEET 2.

WITNESSES: WAMW I// ATTORNEY R. BECKER.

FEEDING MECHANISM FOR SEWING MACHINES.

APPLICATION FILED NOV; 19, 1918.

3 SHEETS-SHEET 3.

WITNESSES: INVENTOR ATTORNEY NTTE STATES PATENT OFFICE.

BIUDOLTH BECKER, 01E ROSELLE PARK, NEW JERSEY, ASSIGNOR TO THE SINGER MANUFACTURING COMPANY, A CORPORATION OF NEW JERSEY.

FEEDING MECHANISM FOR SEWING-MACHINES.

earner.

Specification of Letters Patent.

Patented Nov. 15,1921.

@rlglnal application filed November 5, 1917, Serial No. 200,273. Divided and this application filed November 19, 1918. Serial No. 263,135.

T 0 all whom it may concern Be it known that I, RUDOLPH BECKER, a citizen of the United States, residing at Roselle Park, in the county 6f Union and State of New Jersey, have invented certain new and useful Tmprovements in Feeding Mechanism for Sewing-Machines, of which the following is a specification, reference being had therein to the accompanying drawings.

This application is a division of my application Serial No. 200,273, filed November 5, 1917, and relates to the feeding mechanism for advancing the work a stitch length at a time.

It aims to provide a new and improved mechanism which is simple in construction and both durable and powerful in operation.

It also aims to provide a feed-regulator which is accessibly located at the front of the machine and conveniently operated.

The invention further aims to provide adj ustments enabling the projection of its teeth above the plane of the throat-plate being nicely determined to suit the requirements of the different grades of straw braid the machine is designed to stitch together.

The feed-dog isadjustably supported on a lever which is actuated by a rocker from an eccentric on the main-shaft and thereby.

work-advancing movements are imparted to it. imparted to the feed-dog from a substantially vertically arranged pitman embracing a second eccentric on the main-shaft. A link connects the lower end of the vertically arranged pitman with the lever on which the feed-dog is mounted being connected to the latter adjacent the feed-dog.

The invention is illustrated in the accompanying drawings, in which Figure 1 is a perspective of a straw-braid sewing machine to which the feeding mechanism has been applied. Fig. 2 is an end elevation of the machine with the overhanging bracket-arm omitted. Fig. 3 is a perspective view of the feed-dog mounted on the lever which carries it. Fig. 1 is a vertical transverse section showing the feed-regulating lever. Fig. 5 is a rear side elevation, partly in section, showingthe location of the vertically arranged lifting pitman and Fig. 6 is a detail in perspective of the vertically arranged lift- ,ing itman and a link actuated thereby,

Vertical components of motion are Fig. 7 is a detail of a segment plate for gaging the feed regulator.

The machine in which the invention has been incorporated is provided with the usual overhanging bracket-arm 1 supported at one end by a vertical standard 2 rising from a base 3. Suitably journaled in the frame of the machine is a main-shaft 4 which is driven through a belt-wheel 5 on one end thereof, the opposite end of the main-shaft terminating substantially flush with the opposite exterior face of the frame of the machine.

The stitch-forming mechanism comprises a hooked needle 6, an eye-pointed needle 7 actuated from below the throat-plate 8 and cooperating with the needles above the presser-foot 9 are a pair of angularly disposed loopers 10 all of the form and arrangement shown in my parent application above mentioned and all actuated by mechanism such as is therein fully disclosed.

The feed-dog 11 is cut away at one corner to clear the needles 6 and 7, see Figs. 2 and 3. Its usual serrated upper face is gouged out in the line of seam-formation directly in rear of the needles alongside of which stand prongs 12 insuring against slippage of the work during the step-by-step advance thereof. A depending post 13 integral with the dog is fixed by a screw 14 between the flanges 15 on a block 16 which is clamped by a screw 17 in the channeled head 18 of a feed-dog supporting member in the form of a link 19 with an enlarged and offset portion at one end constituting the above mentioned head 18. To permit adjustment of the feed-dog relative to the channeled head 18, see Fig. 2, the block 16 is slotted as indicated at 20 to receive the clamping screw 17 For effecting a nice or minute adjustment of the feed-dog relative to its support and to thus determine its maximum projection through and above the throatplate, a turn-screw 22 is threaded into the block 16 and its restraining collar 23 is rotatably mounted in the slots 24: of the channeled head 18.

The feed-dog is moved in an elliptical path, the resultant of combined horizontal and vertical components of motion and characteristic of four-motion feeding mechanisms.

Fol lifting the feed-dog the eccentr c 25,

indicated indotted linesin Fig. 2' is embraced by a pitman 26 extending downwardly and laterally a relatively considerable distance, in the present instance about two and three-fourths inches, in between the sides of a groove 27 in the disk-like head 28 of a swivel-pin 29 (Fig. 6 only) mounted-in the frame where the pitman is provided with a pivotal connection '30 to an upwardly extending link 31' bent intermediate its ends as shown at 32 in a direction away from the pitman 26 and extending upwardly to its point of pivotal connection with the feeddog supporting member. The pivotal connection between the link and the feed-dog supporting member is in the form of a relatively long pin 33, set-screwed as indicated at 34 fast to the link 31 and having a head 35 at its opposite end restraining endwise movement of the boss 36 of the feed-dog supportingmember 19 embracing the pin. The upper end of the link 31 above the bend 32 is steadied between a vertical face of the lug 37 integral with the frame and a U-shaped plate 38 screwed thereto as shown. The feed-dog is given its vertical components of motion or lifting movements through these connections.

For imparting feeding movements to the dog the eccentric 39, Fig. 4 on the mainshaft is embraced by a pitman 40 extending rearwardly a relatively considerable distance, in the present instance about 4 inches, Where a block 41 is pivoted so as to slide in an arcuate slot 42 in a feed rocker 43 pivoted at its lower end to the frame of the machine as shown at 44. At the upper end of the rocker the feed-dog supporting member or link 19, is pivoted on the pin 45. At the front end of the link 19 the before mentioned boss 36 extends laterally into proximity with the feed-dog where the channeled head 18, adjustably supporting the feed-dog, is located. Through these connections the feed-dog is given its horizontal components of motion or feeding movements which it. is to be observed are substantially flat because of the relative great length of the vertically arranged link 31 carrying the pin 33 or movable fulcrum of the feed-dog supporting member.

A feed regulator is provided for varying the length of stitch, such variations occurring at the rear end of the feed-stroke because the center of curvature of the slot 42 in the rocker 43 coincides with the center of the feed eccentric 39 when the same is at its most forward position and consequently the feed-dog always rises and engages the Work at the same point relative to the paths of the needles. The feed regulator is in the form of a lever 46,, Fig. 4 pivoted on themainshaft 4 between collar 47, Fig. 1 and the feed-eccentric 39 and having a fork 48 curved as shown at the end of its long arm embracing a friction roll 49 carried by the block 41 in the slotted feed-rocker 43 so that the operator is enabled on manipulating the opposite end of the lever to shift the block to and from the fulcrum of the feed-rocker .to vary thelength of feed 01' stitch. Convenient control-of the feed regulator is provided by extending a rod 50, Fig. 4 secured in the short arm 51 of the lever through a slot 52 in the front wall of the frame in register with which slot is a correspondingly shaped opening in a segment plate 53 secured by screws 54, to the frame and provided on opposite sides of the elongated opening with a series of sockets 55, Fig. 7 A ,handle 56 is sleeved on the end of the rod 50 and a coiled spring 57 is interposed between the bottom of the socket in the handle and the head of a screw 58 threaded into the rod- 50. A pair of diametrically disposed pins 59 are arranged on the inner end of the handle 56 and are adapted to seat in the sockets 55 in the plate. These sockets and pins may be of such size, shape and spacing as to permit of any desired variations in the length of stitch.

Having thus set forth the nature of the invention, what I claim herein is 1. In a feeding mechanism for sewing machines, a feed-dog, a main-shaft, means for imparting feeding and lifting movements to said feed-dog including a feed-rocker provided with a slot and pivoted a substantial distance in rear of the main-shaft, a slideblock fitted ,to the slot in said feed-rocker, an eccentric element on said shaft, a strap connecting said eccentric element and said slide-block, and a lever pivoted on said shaft for adjusting said slide-block in said slot, a segment-plate having a series of sockets located at the front of the machine, an operating handle on said lever, and one or more yieldingly supported detent-pins on said handle adapted to seat in said sockets and hold said lever in an adjusted position.

2. In a feeding mechanism for sewing machines, a feed-dog, a feed-dog supporting member, a main-shaft, mechanism for imparting feeding movements to the dog, and mechanism for imparting lifting movements to the dog including an eccentric element on said main-shaft, a grooved member swiveled in a fixed part of the machine and spaced a substantial distance below said main-shaft, a strap operated by said eccentric element at one end and at its opposite free end fitted to the groove in said member, a pin arranged in the free end of said strap, and a link connected to said pin and to said feed-dog supporting member adjacent the feed-dog.

3. A feeding mechanism for sewing machines comprising a feed-do a feed-dog supporting member, means or imparting feeding movements to the dog and means for imparting lifting movements to the dog including a swivel-pin provided with a guide, a driving member cooperating with the guide and guided thereby, a pivot-pin carried by said driving member, and a link connecting said pivot pin to said feed-dog supporting member.

4. In a feeding mechanism for sewing machines, a feed-dog, a feed-dog carrying link having an offset head, said dog being supported by said offset head, means for imparting feeding movements to the dog, and means for imparting lifting movements to the dog including a pitman, and a link, said link and pitman being pivotally connected together at one end and offset laterally at their other ends.

5. In a feeding mechanism for sewing machines, a feed-dog, a feed-dog carrying link having an offset head, said dog being supported by said offset head, means. for imparting feeding movements to the dog, means for imparting lifting movements to the dog including a pitman and a link, link and pitman being pivotally connected together at one end and offset laterally of their other ends, and means for steadying the offset portion of the link against displacement or flexure ina direction transverse the direction of feed.

6. In feeding mechanism ,for sewing machines, a feeddog, a feed-dog supporting member, a shaft, means for imparting feeding movements to the dog, and means for imparting lifting movements to the dog comprising a driving element on the shaft, a swiveled guide member, a driving means leading from the driving element to the guide member, and guided thereby, and a link having pivotal connection with said driving means and connected to the feed-dog supporting member.

In testimony whereof, I have signed m name to this specificatlon.

RUDOLPH BECKER.

said 

